WASHINGTON DC —
As malaria rates decline across much of Africa, a new study seeks to fight another problem.

Drug-resistant bacteria are a growing concern as antibiotics have become the automatic choice for treating a child with a fever.

Research from Tanzania, published in the New England Journal of Medicine, shows that most illnesses are caused by viral infections. Antibiotics do not kill viruses, and overuse of these important drugs is decreasing their effectiveness.

Success and challenge

Until recently, malaria has been so prevalent in many African countries that health workers assumed any child with a fever had it. But after a decade of intensive efforts and billions of dollars of global investment, malaria rates are declining across the continent.

A recent report found lower rates in 40 of 44 African countries studied.

But that leaves doctors with a new set of challenges: If malaria is not causing a child’s fever, what is? And how should it be treated?

“Their tendency is to prescribe an antibiotic instead of an anti-malarial,” said infectious disease expert Valerie D’Acremont with the Swiss Tropical and Public Health Institute, “which is also bad, because we just shift from one problem to the other.”

Alarming resistance

Where D’Acremont works in Tanzania, antibiotic resistance is so serious that she estimates half her patients with pneumonia do not respond to the first-line drug. Second-line drugs are more expensive or not available.

But without better data on what made Tanzanian kids sick, no one could say how often antibiotics were the wrong treatment.

So D’Acremont and her colleagues studied about 1,000 children seen at two clinics in Tanzania, one urban and one rural. They performed exams and blood tests, cultures, molecular tests and more to identify all the types of illness and their causes.

Less is more

About 10 percent of the children had malaria.

For the rest, far more illnesses were viral than bacterial. About half had respiratory infections, mostly caused by viruses such as influenza.

So the authors recommend that except in severe cases, children should be sent home without antibiotics and seen again a few days later if they don't improve on their own.

Severe cases present a challenge, and D’Acremont says new tools are needed to help diagnose them.

“But this does not justify prescribing antibiotics to all just to be on the safe side,” she said. “We cannot afford that.”

Outdated message

“For the last 30 years at least we have been telling mothers of young children in Africa, ‘If your child has a fever, get treatment for malaria within 24 hours,’” said Matthew Lynch, director of the Global Program on Malaria at Johns Hopkins University, who was not involved in the research. “That message is now not only outdated, but wrong.”

That creates a communication challenge for public health workers, Lynch says, and also calls for a major effort to ensure caregivers seek testing to find out what is causing a child’s fever before deciding on treatment.

That's not to say that malaria is no longer a threat.

"There are plenty of places in Africa where malaria is still horrible," says economist Jessica Cohen at the Harvard School of Public Health. Her studies in parts of Kenya and Uganda found 80 percent of people coming to drug shops for medication tested positive for malaria.

And while public health officials have shifted away from recommending anti-malarials to anyone with a fever, Cohen says that shift may have gone a bit too far.

"Under-treatment is a real problem, too, and is likely the main driver of lingering child mortality from malaria," she said.

The price of success in the fight against malaria is that treating fevers has become much more complicated.